Overview
Fertilizer and agrochemical is a pillar of Chinese basic industry — urea production alone exceeds 60 million tons annually. Key measurement points include urea solution tank farm level + density, ammonia synthesis loops, pesticide intermediate reactor concentration (methyl chloroformate, pyrethroids, organophosphates) and compound fertilizer blending. Leading Chinese producers (Xinlianxin, Hualu Hengsheng, Yangmei, Luxi, CNOOC Chemicals, Lier Chemical, Yangnong) rely on inline density measurement for production stability and quality control.
Process challenges
- Urea tanks have tall columns (10-25 m) — production needs simultaneous density + level, not just level
- Urea readily crystallizes at 60-80°C — diaphragms and intrusive probes scale and clog
- Ammonia synthesis runs strongly alkaline with NH₃ gas — corrodes common wetted materials
- Pesticide reactors run batch — every batch needs traceable concentration history
- Nuclear gauge phase-out is accelerating in fertilizer plants
Recommended solutions
| Measurement point | Principle | Models |
|---|---|---|
| Urea solution tank density + level | DP (double flange) | PS7300 |
| Ammonia solution concentration | Tuning fork + alkali coating | PS7400 |
| Pesticide reactor concentration | Spectroscopic / refractive | PS7100 / PS7110 |
| Compound fertilizer blending | Ultrasonic sound velocity | PS7020 |
| Liquid ammonia storage density | Tuning fork + high-pressure Ex | PS7400 |